The maintenance of a private swimming pool, especially in regard to the chemistry involved, is a complex, time-consuming and expensive routine when handled in the conventional manner.
During the warmer season in particular, the water must be checked almost daily to determine the pH level and chlorine content. Unless these factors are carefully controlled, the growth of bacteria and algae in the pool will be excessive with the result that a hazard to health is produced. In addition, the water and the surfaces of the pool become discolored and unsightly. To maintain the required pH level, frequent addition of acid is required. The chlorine is added chemically, typically in the form of sodium hypochlorite. Because the chlorine is usually added intermittently by this method, a compromise must be accepted in terms of the instantaneous chlorine level with an undesirably high level experienced after the chlorine is added and an undesirably low level existing just prior to the addition. In the interest of producing a leveling effect, certain stabilizing chemicals are added which delay the release of the chlorine, hopefully with an economy realized because of the increased total effectiveness of the chlorine added. The stabilizer can build up excessively, producing a condition known as "chlorine lock", in which the chlorine is tied up and not available as an oxidizing agent. This and other conditions require special corrective procedures. In addition, "shock treatments" involving super-chlorination are required periodically to destroy certain types of algae which develop resistance to the relatively constant lower level of chlorination. Algaecide inhibitors are also recommended along with the "shock treatments".
The foregoing routines are expensive and time-consuming and they tend to bewilder the average pool owner. If he fails to follow the proper procedures faithfully, corrective measures must be taken which are even more expensive in the long run because of the resulting deterioration of the pool itself.
In addition to the foregoing disadvantages of the conventional chlorination procedures employed by the typical home pool owner, the special chemicals added over and above the chlorine itself produce undesirable effects on the pool walls and on clothing, and they are irritating to the skin, eyes and sinuses of those using the pool.
It is recognized that a more desirable result in terms of pool chemistry may be realized if chlorine is introduced as a gas directly into the water rather than in combination with other chemicals. This method is utilized by professional pool maintenance operators, especially in connection with the treatment of the larger public pools. Because of the hazards involved in the handling of the pressurized tanks of chlorine gas and because of the toxicity of the gas, however, this method has not been widely applied in the case of the smaller private pools.
In recent years, small chlorine generators have become available that are intended for operation adjacent to the private swimming pool. These small generators supply a continuous supply of chlorine to the pool with the intended purpose of holding the clorine content as near as possible to the optimum level.
This invention relates to electrolytic chlorine generators of the above mentioned type and, more particularly, to an improved version incorporating a porous ceramic diaphragm in combination with a flame or plasma deposited cathode.